When is an miRNA not an miRNA? - definition of energy state (Jun/10/2005 )

Hi,

I read a paper where it defined miRNAs as having to have a folding free energy of at least 25 kcal mol-1 (using RNAfold).

My question is this. If the miRNA had a folding free energy <25 kcal mol-1, would it lose secondary structure and no longer be able to function?

I would love to be referred to original papers discussing the energy fucntions of miRNAs if anyone has them.

Thanks

tricky question eh? Come on guys, get stuck in!!